Arm rest



April 8, 1947. L. B. STALLCUP ARM REST Filed April 1, 1946 '2 Sheets-Sheet 1 INVENTOR L. B. STALLCUP Apri 8, 1947.

ARM REST Filed April 1, 1946 INII/ENTOR.

Patented Apr. 8, 1947 UNITED STATES PATENT OFFICE ARM REST Lester B. StaIlcup, Phoenix, Ariz. I u appneation'a rn 1 1946,, Serial No. 658,659.

3 Claims.

This invention pertains; to arm rests for use on operating chairs: in connection with. intravenous administration. of anesthetics; or the like.

It has for its objects, first, the provision. of an arm rest which. can be clamped to the arm of a dental or physicians chair, and will receive and hold the arm of the patient in a natural, relaxed andv convenient position adjacent injection apparatus. Second, the provision of an arm. rest pairing a. lower part adapted to be removably attached to a dental. chair arm, an upper part adapted to receive and hold the arm of a; patient sitting. in said. chair, and an adjustment mechanism; between. said two parts so that bothnthe; longitudinal angleand the lateral anglebetween said .parts may be adjusted. Third, the provision of a device as above mentioned having abase.adaptedforeasy attachment and detachment to. a chair arm, with an arm board joined thereto so that both the longitudinal and lateral plane of the arm board may be adjusted relative to said: base;- and with a bracket -adapted to receive. and retain intravenous injection apparatus positioned along. one side of said. base in convenient position for operation.

Other objects will appear hereinafter.

I attain the foregoing objects by means of the device illustrated in the accompanying drawings in which Figure 1 is a side elevation showing the device applied to a chair arm;

Figure 2, a side elevation with portions sectioned off the near face to show interior construction;

Figure 3, a plan view of the device as shown in Figure 2 with portions broken away to show interior construction and Figure 4, an end sectional elevation taken substantially on line 4-4 Figure 2.

Similar numerals refer to similar parts in the several views.

The base 2 is preferably made of cast aluminum. It has an arcuate plan conformable to the plan of a chair arm 3. from an upper plate 4 of this base on both sides and at the front. This forms a shell which fits over the chair arm. The rear is open so that the under face of top plate 4 will rest on the top face of the chair arm. On the inner face of the inner rim 6 there are stationary pads 8 and 9 adapted to contact the inner side of the chair arms. Threaded into the outer rim In there is a screw II which carries a pad l2 positioned longitudinally between inner pads 8 and 9. Op-

A rim depends eration of this screw by knurled nut i4 forces pad l2. to engage the outer sidejface of ehair arm, 3. p

In the forward p-artof plate. 4 there is a semispherical socket i=5. which receives a rounded semi-ball l6, attached to the underside of the arm board il. A screw IE is attached by a universal joint is to a lug 28 on the underside of the arm board, extends downward through a boss 2| on. the bottom of socket l5, and carries a knurled nut 23 on its lower end. A hole 2- 1 is formed in the center of socket L6 large enough to give suflicient rotative movement. in socket I5 to allow a considerable longitudinal and, lateral movement of arm board ll. The extent of. this movement is governed by the size. or this hole. When nut. 23 is tightened up the contacting surface of the semi-ball l5 and socket l5- are broughtfinto frictional engagement sufiicient to hold the hoardv in the position desired. To assist in supporting the weight of the patients elbow an additional support is provided at the rear of the arm board. This consists of a rod 3%! having a ball 3| at its upper end. operative in a socket 32 formed on the underside. of the board. near its outer edge. .The rod slides in a ball 33; held in a socket formed in the upper plate of base- 2 near the outer edge. Ball 33 has a boss 34 through which the rod extends, and a set screw 35 threaded radially into this boss holds the rod at the desired position along its length.

From this arrangement it will be seen that the ball and socket joint 31 at the forward end of the arm board provides a universal joint, allowing movement in three planes, i. e.: longitudinally, laterally and pivotally. The joint may be tightened and the board secured at the adjusted position. The ball mounted rod 30 will follow the movement of the rear of the arm board and support it against vertical displacement, but obviously will not hold it against lateral twisting movement. This, however is unnecessary because the forward joint 31 is adequate to hold the arm against turning and lateral tilting.

A shelf at is added to the outside of base 2 near the forward end. This is provided with a dove tail slide 4i adapted to receive the underside of a syringe frame 42 shown in Figure 1. The syringe frame is shown only generally here since its structure pertains to a different art. This merely illustrates one use of the arm rest, and to those familiar with the art, many othr uses will be apparent.

In use the base 2 is clamped to the chair arm 3, by operation of screw I I. The patient is placed in the chair with his arm 45 resting on arm board l1. Slots 4B in the board receive the cufi 41 and this is placed over the patients wrist-so that the arm lays on the board with the palm side of the hand upward. The board is then raised, tilted and rotated until the patients arm rests in the most comfortable position. When this position is attained nut 23 is set to lock the board in position, and set screw 35 seton rod 30. The cuff may'then be tightened as desired, and the syringe connections applied according to the practice.

Having now fully described my invention and explained its use I wish to be limited only bythe following claims.

I claim:

1. An adjustable arm rest for operating chairs comprising, in combination, a base having a hollow under side adapted to conform to the contour of an operating chair arm, a screw clamp operative on said chair arm to secure said base thereon, an arm board attached to said base near the forward end by a semi-ball and socket joint, a screw and nut operative in said joint adapted to secure said ball and socket joint by frictional engagement of its contacting surfaces, a vertical supporton the rear of said arm board including a rod mounted by a ball joint on the rear of said arm board slidably mounted in a ball joint on the rear of said base and means for engaging said rod in said'slidable mount.

2. An adjustable arm rest for operating chairs, comprising in combination, a base shaped to conform to the contour of the chair arm having a depending rim at the front and along the side edges, a socket formed in the front portion thereof, arm gripping pads on the inner face of the inner depending rim, and a gripping pad mounted on a transverse screw threading thru said outer rim; an arm rest having means for attachment of a wrist cuff, a semi-ball formed on the lower side of its front portion provided with a central opening, a tightening screw secured Within said semi-ball by a universal joint, a nut operative on said screw below said base socket to draw said ball into said socket; means for sup-- porting the rear of said arm board including a rod retained in a ball joint on the underside of said board, a ball having a boss with a rod clamping screw, mounted in a socket in said base, and adapted to slidably receive said rod; and a shelf extending outward from the outer edge of said base adapted to receive a syringe.

3. An adjustable operating chair arm rest to hold a patients fore-arm in relaxed position accessible for intravenous injection techniques, comprising in combination, a base plate conforming to the plan and contour of an operating chair arm having means for clampable attachment thereto, an outwardly extending instrument holding shelf, and a forward projecting portion provided with a semi-spherical upwardly opening socket with a depending boss thereon having a hole to receive a locking screw, an arm rest plate adapted to receive and retain the patients forearm, and means for attaching said arm rest plate to said base plate to secure lateral and horizontal adjustment including a semispherical ball on said arm rest plate operative in said base plate socket adapted to frictional engagement therein, a circular opening in the center of the bottom of said ball portion, a tightening screw extending from the underside of said 1 arm plate centrally alined with said opening, having a universal joint concentric with said ball and socket vand a threaded portion extending thru the boss on said socket, and a hand nut thereon, together with a height adjusting bar at the rear of said arm plate secured by a ball and socket joint therein, depending therefrom and secured in a boss mounted on a ball and socket support on the rear portion of said base.

LESTER B. STALLCUP.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Ntunber Name Date 1,706,634 Sells Mar. 26, 1 929 1,374,907 Cofrode Apr. 19, 1921 1,887,022 Hoffman et al Nov. 8, 1932 848,173 Hubbell Mar. 26, 1907 

